Electromagnetic valve with precisely adjustable magnetic gap

Abstract

The application discloses a magnetic gap adjustable electromagnetic valve, comprising an electromagnetic assembly and a reversing valve, the reversing valve is a two-position three-way reversing valve, and the electromagnetic assembly drives the valve position switching of the reversing valve through a push rod. The electromagnetic assembly comprises a magnetic isolation sleeve, a pole shoe, a static iron core and a dynamic iron core, one end of the push rod is limited in the dynamic iron core through a magnetic gap adjusting assembly, the other end of the push rod is connected with the reversing valve through the static iron core, the magnetic isolation sleeve is arranged between the static iron core and the pole shoe, the dynamic iron core is movably arranged in the pole shoe, the middle part of the static iron core and the pole shoe and the outer side of the whole magnetic isolation sleeve are provided with a framework, a first coil and a second coil are wound on the framework, the first coil and the second coil are connected in parallel and are not simultaneously electrified during work; the outer side of the static iron core and the pole shoe is further provided with an outer shell, the outer shell wraps the framework and is provided with a lead hole. The magnetic gap adjusting assembly is used for realizing the accurate adjustment of the magnetic gap, the super-high machining precision of parts is not needed, and the machining difficulty, assembly difficulty and production cost are effectively reduced.

Description

Technical Field

[0001] This invention relates to an electromagnetic valve with precisely adjustable magnetic gap. Background Technology

[0002] The magnetic gap plays a decisive role in the electromagnetic attraction force between the moving iron core and the stationary iron core: when the magnetic gap is too large, the electromagnetic attraction force is insufficient, and the moving iron core cannot overcome the spring force to complete the positioning action; when the magnetic gap is too small, the residual magnetism is too strong after the moving iron core and the stationary iron core are attracted, which causes the moving iron core to be unable to reset smoothly, affecting the normal operation of the solenoid valve.

[0003] In existing solenoid valves, the electromagnetic control component includes a magnetic sleeve, an electromagnetic coil, a push rod, a solenoid valve, and a solenoid valve connecting rod. This structure ensures the air gap by improving the machining accuracy of all parts in the electromagnetic control component. This method, which relies on the machining accuracy of parts, has significant drawbacks: First, it requires a large number of high-precision parts, significantly increasing the complexity of the machining and assembly processes; second, it imposes stringent dimensional accuracy requirements on each part, directly driving up manufacturing costs; and third, once machining is complete, the magnetic gap cannot be adjusted, and assembly errors or wear of parts during use will directly lead to a decline in the performance of the solenoid valve or even its failure. Summary of the Invention

[0004] The purpose of this invention is to address the problem that the magnetic gap of a pre-existing iron core cannot be adjusted, and to provide a solenoid valve with a precisely adjustable magnetic gap. Through a specialized magnetic gap adjustment structure, the magnetic gap can be precisely adjusted without relying on ultra-high precision parts processing, thereby reducing production difficulty and cost, while improving the adaptability and service life of the solenoid valve.

[0005] The technical solution of the present invention: The present invention provides a solenoid valve with precisely adjustable magnetic gap, comprising an electromagnetic component and a reversing valve, wherein the reversing valve is a two-position three-way reversing valve, and the electromagnetic component drives the valve position switching of the reversing valve via a push rod.

[0006] The electromagnetic assembly includes a magnetic shielding sleeve, pole shoes, a stationary iron core, and a moving iron core. One end of the push rod is limited within the moving iron core by a magnetic gap adjustment assembly, and the other end of the push rod passes through the stationary iron core and connects to the reversing valve. The magnetic shielding sleeve is located between the stationary iron core and the pole shoes, and the moving iron core is movably installed within the pole shoes. A frame is provided in the middle of the stationary iron core and the pole shoes, as well as on the outer side of the entire magnetic shielding sleeve. A first coil and a second coil are wound on the frame. The first coil and the second coil are connected in parallel and are not energized simultaneously during operation. A shell is also provided on the outer side of the stationary iron core and the pole shoes. The shell encloses the frame and has lead wire holes.

[0007] The magnetic shielding sleeve is made of non-magnetic stainless steel and is used to isolate the magnetic circuit between the stationary iron core and the pole shoes, ensuring that the main magnetic circuit is closed and does not disperse.

[0008] The magnetic gap adjustment assembly includes a connector and an adjusting screw. The connector is fixed to the end of the moving iron core facing away from the stationary iron core. A threaded hole is machined in the center of the connector, and the adjusting screw fits into the threaded hole. One end of the adjusting screw contacts the push rod, and the other end extends out of the connector and is fitted with an elastic washer and a fixing nut. By turning the adjusting screw a certain number of times, its depth in the connector can be adjusted, thus precisely changing the magnetic gap between the moving and stationary iron cores. The adjustment error range can be controlled within ±0.01mm.

[0009] The pole shoe is also machined with an adjustment hole, which is aligned with the fixing nut and fitted with a plug through an internal thread. The adjustment hole is a stepped hole, and the outer wall of the plug matches the shape of the adjustment hole. The end face of the plug extending into the pole shoe is also machined with a circular groove to accommodate the fixing nut, which facilitates the adjustment operation and also protects the adjustment component.

[0010] The push rod is connected to the reversing valve through a support base. The support base is a round cap shape, which serves to fix and guide the push rod, ensuring that the push rod moves in a straight line.

[0011] The outer shell is equipped with sealing rings between itself, the pole shoe, and the stationary iron core, which improves the sealing performance of the electromagnetic components and makes them suitable for complex working environments such as humid and dusty environments.

[0012] The combination of the pole shoe and the stationary iron core is an annular stepped groove. The magnetic shielding sleeve, the frame, and the outer shell are sequentially assembled in the stepped groove, making the overall structure more compact and easier to assemble.

[0013] The electromagnetic circuit of the electromagnetic component is composed of soft magnetic materials such as stationary iron core, moving iron core, pole shoe, outer shell, first coil or second coil. After the electromagnetic component is assembled, an initial magnetic gap is reserved between the moving iron core and the stationary iron core to prevent the residual magnetism of the two from being too large after the electromagnetic force is applied, so that they cannot be reset normally.

[0014] The first and second coils are redundantly designed. When one coil is damaged, the external power supply can be used to replace the other coil, thus extending the service life of the electromagnetic components.

[0015] When a 24VDC pulse current is applied to the electromagnetic component, the moving iron core is attracted to the stationary iron core under the action of the electromagnetic field. The moving iron core drives the magnetic gap adjustment structure to push the push rod, so that the reversing valve switches to the first valve position. After the power is cut off, under the action of the reset spring, the push rod pushes the magnetic gap adjustment structure in the opposite direction, so that the moving iron core is reset, and the reversing valve switches to the second valve position.

[0016] The beneficial effects of this invention are as follows: Precise adjustment of the magnetic gap is achieved through the magnetic gap adjustment component, eliminating the need for ultra-high machining precision of parts, effectively reducing machining difficulty, assembly difficulty, and production costs. Simultaneously, the adjustment error is controlled by the thread precision of the adjusting screw, reducing machining requirements and ensuring the control accuracy of the solenoid valve. The first and second coils employ a redundant design; when one coil fails, the other can be switched to operate, extending the service life of the solenoid valve and improving the reliability of equipment operation. The overall structure is compact with good sealing performance. The sealing ring design between the outer shell and the pole shoe / stationary iron core allows it to adapt to various complex working environments, broadening its application range. Magnetic gap adjustment is convenient; the adjusting screw can be turned through the adjustment hole on the pole shoe, and after adjustment, it is locked by the fixing nut and elastic washer to ensure the stability of the magnetic gap. Even if gap deviation occurs after long-term use, it can be readjusted and corrected. Attached Figure Description

[0017] Figure 1 This is a cross-sectional view of the electromagnetic component of the present invention.

[0018] Figure 2 This is a cross-sectional view of the magnetic gap adjustment structure of the electromagnetic component of the present invention.

[0019] Figure 3 This is a schematic diagram of the solenoid valve of the present invention.

[0020] Reference numerals: 1-Electromagnetic assembly, 11-Stationary iron core, 12-Magnetic shielding sleeve, 13-Moving iron core, 14-Connector, 5-Adjusting screw, 16-Elastic washer, 17-Fixing nut, 18-Plug, 19-Pole shoe, 110-Outer shell, 111-First coil, 112-Frame, 113-Second coil, 114-Push rod, 115-Support base, 2-Reversing valve. Detailed Implementation

[0021] Example 1: Reversing Control of Precision Hydraulic System This embodiment is applied to the hydraulic circuit reversing control of a precision hydraulic machine tool, requiring the magnetic gap control accuracy of the solenoid valve to be within 0.05mm ± 0.01mm to ensure the action response speed and position accuracy of the hydraulic actuator.

[0022] Assembly and Debugging: First, complete the overall assembly of the solenoid valve according to the assembly process. Install the magnetic shielding sleeve 12 between the stationary iron core 11 and the pole shoe 19. Fit the frame 112 onto the outside of the magnetic shielding sleeve 12, ensuring the first coil 111 and the second coil 113 are correctly connected in parallel. Unscrew the plug 18 through the adjustment hole on the pole shoe 19. Use a special wrench to turn the adjusting screw 15, adjusting the magnetic gap between the moving iron core 13 and the stationary iron core 11 to 0.05mm according to the hydraulic system design requirements. During the adjustment process, monitor the magnetic gap value in real time using a laser micrometer. Once the value reaches the set value, tighten the fixing nut 17, causing the elastic washer 16 to press against the connecting piece 14, thus locking the adjusting screw 15 in place. Finally, reinstall the plug 18 back into the adjustment hole to complete the assembly and debugging.

[0023] Working process: Connect the solenoid valve to the hydraulic system and connect the external power supply to the first coil 111. When the hydraulic machine tool needs to switch the hydraulic circuit, the control system outputs a signal to supply a 24VDC pulse current to the solenoid component 1. The first coil 111 generates an electromagnetic field. Under the action of electromagnetic attraction, the moving iron core 13 is attracted to the stationary iron core 11, which drives the magnetic gap adjustment component to move synchronously and pushes the push rod 114 to move towards the reversing valve 2, so that the reversing valve 2 switches to the first valve position. The hydraulic circuit completes the reversal, and the hydraulic actuator moves according to the preset trajectory.

[0024] Reset and Redundancy Switching: After the actuator completes its action, the control system cuts off the pulse power, the electromagnetic field disappears, and under the elastic force of the reset spring, the push rod 114 pushes the magnetic gap adjustment component in the opposite direction, causing the moving iron core 13 to reset to its initial position. The directional valve 2 switches back to the second valve position, and the hydraulic circuit returns to its initial state. If the first coil 111 is found to be damaged after long-term use, the external power supply can be switched to the second coil 113. The solenoid valve can be restored to normal operation without replacing the entire solenoid valve.

[0025] Example 2: Pneumatic Control of Automated Production Line This embodiment is applied to the control of pneumatic grippers in an automated electronic product assembly line. The production line environment is dusty, and the opening and closing movements of the pneumatic grippers require high precision. The magnetic gap needs to be adjusted to 0.08mm±0.01mm, and the solenoid valve is required to have good dustproof sealing performance.

[0026] Assembly and Debugging: During assembly, install sealing rings at the connections between the outer casing 110, the pole shoe 19, and the stationary iron core 11 to ensure sealing performance. Adjust the magnetic gap between the moving iron core 13 and the stationary iron core 11 to 0.08mm by turning the adjusting screw 15 through the adjusting hole and measuring the magnetic gap with a dial indicator. After adjustment, tighten the fixing nut 17, ensuring the circular groove of the plug 18 fully accommodates the fixing nut 17 to prevent dust from entering the adjustment assembly. The support base 115 is fixed to the mounting bracket on the production line with bolts, and the push rod 114 precisely aligns with the drive rod of the pneumatic gripper.

[0027] Working process: According to the assembly process instructions, the production line control system supplies a 24VDC pulse current to the second coil 113 of the electromagnetic component 1. The electromagnetic field drives the moving iron core 13 to engage, and the push rod 114 pushes the pneumatic gripper drive rod, causing the gripper to close and pick up the electronic product parts. Due to the precise adjustment of the magnetic gap, the electromagnetic attraction force is stable, and the gripper closing force is uniform, preventing parts from being pinched or falling off.

[0028] Long-term use and maintenance: During long-term use, if the opening and closing accuracy of the gripper decreases due to dust accumulation or slight vibration, the plug 18 can be removed, and the adjusting screw 15 can be finely adjusted to correct the magnetic gap to the set value. This eliminates the need to disassemble the entire solenoid valve, making maintenance convenient. The sealed design of the outer casing effectively prevents dust from entering the electromagnetic component 1, ensuring the cleanliness of the coil and iron core and extending its service life.

[0029] Example 3: Hydraulic reversing control of underwater equipment This embodiment is applied to the reversing control of the hydraulic propulsion system of an underwater exploration equipment. The equipment operates at a depth of 5-10 meters. The solenoid valve is required to have waterproof sealing performance, and the magnetic gap needs to be adjusted to 0.06mm±0.01mm according to the underwater pressure environment to ensure stable operation under underwater pressure.

[0030] Assembly and debugging: During assembly, the installation quality of the sealing ring is carefully checked to ensure that there are no gaps between the outer shell 110 and the pole shoe 19 and the stationary iron core 11, and that the plug 18 and the adjustment hole of the pole shoe 19 are tightly threaded to achieve overall waterproof sealing. Considering the influence of underwater pressure on the magnetic gap, a special underwater adjustment tool is inserted into the adjustment hole to adjust the magnetic gap to 0.06mm. During the adjustment process, pulse electricity is applied multiple times to test the attraction and reset performance of the moving iron core 13 to ensure smooth operation under underwater pressure.

[0031] Working process: After the underwater detection equipment is launched, the control system supplies a 24VDC pulse current to the first coil 111 of the electromagnetic component 1 via a cable. The electromagnetic field overcomes the underwater pressure, driving the moving iron core 13 to engage. The push rod 114 pushes the reversing valve 2 to switch to the first valve position, and the hydraulic propulsion system changes its propulsion direction. After power is cut off, the reset spring drives the moving iron core 13 to reset, the reversing valve 2 switches back to the second valve position, and the propulsion direction returns to its initial state. The non-magnetic stainless steel material of the magnetic shielding sleeve 12 effectively isolates and disperses the magnetic circuit, ensuring the stability of the electromagnetic attraction force. Even in an underwater environment, the magnetic gap does not shift.

[0032] Emergency troubleshooting: If the first coil 111 is accidentally damaged during underwater operation, the control system automatically switches the power supply to the second coil 113, and the solenoid valve continues to operate normally. This prevents the detection equipment from interrupting its mission due to solenoid valve failure and improves the emergency reliability of the equipment. After the mission is completed, when the equipment is brought ashore for maintenance, the plug 18 can be opened to check the status of the adjustment components. If the magnetic gap shows a slight shift due to pressure changes, it can be finely adjusted and corrected in time.

Claims

1. A solenoid valve with precisely adjustable magnetic gap, characterized in that: It includes an electromagnetic component (1) and a reversing valve (2), wherein the reversing valve (2) is a two-position three-way reversing valve, and the electromagnetic component (1) drives the valve position switching of the reversing valve (2) through a push rod (114); The electromagnetic assembly (1) includes a magnetic shielding sleeve (12), a pole shoe (19), a stationary iron core (11), and a moving iron core (13). One end of the push rod (114) is limited within the moving iron core (13) by a magnetic gap adjustment assembly, and the other end of the push rod (114) passes through the stationary iron core (11) and is connected to the reversing valve (2). The magnetic shielding sleeve (12) is located between the stationary iron core (11) and the pole shoe (19). The moving iron core (13) is movably installed within the pole shoe (19). A frame (112) is provided in the middle of the core (11) and pole shoe (19) and on the outside of the entire magnetic shielding sleeve (12). A first coil (111) and a second coil (113) are wound on the frame (112). The first coil (111) and the second coil (113) are connected in parallel and are not energized at the same time during operation. A shell (110) is also provided on the outside of the stationary iron core (11) and pole shoe (19). The shell (110) wraps the frame (112) and is provided with lead wire holes.

2. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The magnetic shielding sleeve (12) is made of non-magnetic stainless steel.

3. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The magnetic gap adjustment assembly includes a connector (14) and an adjusting screw (15). The connector (14) is fixed to one end of the moving iron core (13) opposite to the stationary iron core (11). A threaded hole is machined in the center of the connector (14), and an adjusting screw (15) is fitted inside the threaded hole. One end of the adjusting screw (15) contacts the push rod (114), and the other end extends out of the connector (14) and is fitted with an elastic washer (16) and a fixing nut (17).

4. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The pole shoe (19) is also machined with an adjustment hole, which is directly opposite the fixing nut (17) and is fitted with a plug (18) through an internal thread.

5. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The adjustment hole is a stepped hole, and the outer wall of the plug (18) matches the shape of the adjustment hole. The end face of the plug extending into the pole shoe (19) is also machined with a round groove to accommodate the fixing nut (17).

6. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The push rod (114) is connected to the reversing valve (2) through the support seat (115), which is a round cap shape.

7. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: A sealing ring is provided between the outer shell (110), the pole shoe (19), and the stationary iron core (11).

8. The solenoid valve with precisely adjustable magnetic gap as described in claim 1, characterized in that: The combination of the pole shoe (19) and the stationary iron core (11) forms an annular stepped groove, and the magnetic shielding sleeve (12), the frame (112), and the outer shell (110) are sequentially assembled in the stepped groove.

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